Machine for filling luncheon dough into mold cans

ABSTRACT

An apparatus for filling food products into molds by a stuffing horn that extends completely within a mold and feeds the food product into the mold as it is retracted. A close-fitting cover plate is then put on the mold while the stuffing horn holds the food product in the mold under pressure.

[ Sept. 5, 1972 United States Patent Good 12/1954 Allbright...............99/351 UX 9/1957 Allbright et al..............220/ /219 [54] MACHINE FOR FELENG LUNCHEON DGUGH INTO MOLD CANS 3,039,382 6/1962 Simon et 3,166,007 1/1965 [72] Inventor: Paul F. Good, Lutherville, Md.

l-lawley et a1. 100/219 3/1966 141/283 141/283 X 3/1968 Hawley..................

[22] Filed: May 25, 1970 [21] Appl. N0.: 40,135

3,385,202 5/1968 Foldenauer..................99/35l 3,480,449 11/1969 Sumption ....................99/ 3,485,274 141/283 X 12/1969 Traulos..................

stuffing horn that extends completely within a mold a n .w m m o u m H o o m m. i H m m m T M U C r mm a mm r c M W a mA [A 114N111 l a 3 R9 mzmm um Mam ww w m m m U U mm References Cited and feeds the food product into the mold as it is UNITEDSTATESPATEN'IS retracted. A close-fitting cover plate is then put on the mold while the stuffing horn holds the food product in the mold under pressure.

2,635,799 Hoy .......................l4l/283 X 2,669,749 Houland.................,......17/35 15 Claims, 17 Drawing Figures PATENTEDSEP 5 i972 SHEET 1 BF 6 INVENT OR PauZ F Good PATENTEBSEP sum 3.688.682

SHEEI 2 BF 6 INVENTOR Paul F Good PATENTEDsEP 5 I912 3.688.682

sum 1; or e GI? SUPPLY INVENTOR Paul F Good PA'TENTEDSEP 51912 3.688.682

' SHEET 5 BF 6- INVENT OR Paul F7 Goad PATENTEDsEP 5 m2 SHEET 6 OF 6 IN T] l i w No U n 2 l l Nom INVENTOR Paul 1 Gbad TESS K mm o MACHINE FOR FILLING LUNCHEON DOUGH INTO MOLD CANS The present invention relates to an apparatus for filling food products into molds for subsequent processing and, in particular, to an automatic machine for spraying mold release oil into the molds, automatically filling the molds and automatically positioning tight fitting lids onto molds while holding the molds under pressure; such that after cooking and chilling, uniformity of crosssectional dimensions and uniformity of density along the length of the loaves is greatly improved over methods presently used.

It is presently common practice to fill molds with food products, cook and chill the loaves, then remove the loaves from the molds for slicing and grouping the slices into groups or stacks of predetermined weights. in this connection, various statutes and regulations require that each group of slices must have the weight specified on the packaging when offered to the consumer. For efficient production, the weights of the stacks of food must. not greatly exceed the specified weight. The weight in excess of the specified weight is usually referred to as give-away weight. With modern slicing methods, the give-away can be reduced by producing loaves of uniform density and cross-section along their length. The lids and molds that are normally used allow leakage and loss of moisture at the ends of the loaves such that the dozen or so slices at the ends of the loaves are underweight and the stacks of food formed from these slices will be underweight. They must be manually corrected by adding a partial slice of product or else by adding a thicker slice of product to bring the stack to the required weight. This correction is not only costly labor-wise, but also detracts from the appearance of the product.

The usual methods of producing loaves of food products produce loaves that are not uniform in cross-.

section and density along the length of the loaves because there are no provisions for maintaining a pressure in the molds while the lids are positioned on the molds. For example, the mold stuffing apparatus shown in l-lawley U.S. Pat. No. 3,373,777 has provisions for developing a pressure in the molds as they are being stuffed, but it is not possible to maintain a uniform stuffing pressure along the length of the loaves because considerable clearance is required between the inside of the molds and the rigid type stuffing horn. As the food product is stuffed, considerable pressure is developed in the mold resulting in leakage between the horn and the insider of the mold. To minimize this, the horn is made quite long to increase the length of the leakage path and therefore reduce the leakage rate. However, as the molds are filled and as the horn nears the filling end of the molds, the leakage path along the horn gradually decreases to zero length, so the leakage near the end of the loaf becomes excessive.

Furthermore, there are no provisions for holding this pressure until the lid is placed on the mold. In operating this apparatus, a mold is placed upon a slidable carriage, the mold is then slid over the stuffing horn, the operator opens a valve in the food supply line to fill the mold, the filled mold is then removed from the apparatus and the lid is manually positioned on the mold.

The instant invention incorporates a flexible horn seal that expands to contact the sides of the molds such that gull mold pressure is maintained during the tained while the lids are automatically placed on the molds. t

The existing types of molds and lids are not suitable for automatic-filling and automatic, loading of the lids. Furthermore, they do notprovide an adequate seal to prevent leakage of moisture and shrinkage at the ends of the loaves. For example, the molds and lids shown in Hawley U.S. Pat. No. 3,166,007 and Foldenauer U.S. Pat. No. 3,385,202'require manual loading of the lids. Also, both patents shown relatively thin plates as sealing members. These plates must of necessity be somewhat smaller than the inside'of the mold to allow for manufacturing tolerances and to allow for some denting and bending of the molds that occur in actual use. For example, some of the plates manufactured according to U.S. Pat. No. 3,166,007 are actually oneeighth inch smaller than the inside dimension of the mold. This clearance allows considerable loss of moisture and consequent shrinkage at the cnds'of the loaves.

'Sumption U.S. Pat. No. 3,462,793 discloses an apparatus in which pairs of lids are inserted into a tubular stuffing horn to make separate, fiat ended sections of food products. This apparatus must be used with flexible type casings and cannot be used to seal off rigid molds that are required for the types of food products referred to in the instant invention.

An object of this invention is to produce a mold filling machine that will greatly reduce the labor required for the filling operation.

Further objects of this invention are to produce a mold filling machine that will produce loaves of food product which are very uniform in cross-section and density along the length of the loaves, will reduce the usual shrinkage during cooking and chilling and will increase the amount of food product that can be put into the molds.

A further object of this invention is to produce a mold filling machine that will automatically maintain a predetermined pressure on the food product in the mold during the stuffing operation.

In general, these objects are obtained by a machine having means for automatically introducing a mold release agent to the inner surface of a mold, means for applying a first lid to one end of an empty mold, means for automatically filling the mold with a food product, hereinafter referred to as food, a means for automatically maintaining a predetermined pressure on the food during the filling operation, and a means for automatically closing the mold while pressure is held on the food product.

This automatic mold filling machine improves the quality of the food loaves and also reduces the labor cost to about 50 percent of the usual mold filling labor cost.

The means by which the objects of this invention are obtained are described more fully with reference to the accompanying drawings in which:

FIG. 1 is a front elevational view of the machine; FIG. 1a is an enlarged detail view of a portion of FIG.

FIG. 2 is a side view of the machine, partly shown in section;

FIG. 3 is an enlarged view, partly in cross-section, of a stuffing horn;

FIG. 4 is a view similar to FIG. 3 of a modified horn;

FIG. 4a is a view of a spider used in the inlet end of the horn shown in FIG. 4;

FIG. 4b-is an enlarged cross-sectional view of a detail shown in FIG. 4;

' FIG. 40 is a schematic view of the air system and hmodulating valve used for the operation of the stuffing om; I

FIG. 5 is a front view of an end of a frame for being fitted to an end of a can for holding acover plate;

FIG. 6 is a cross-sectional view taken on the line 6- 6 of FIG. 5;

FIG. 7 is a side view of a cover plate;

FIG. 8 is across-sectional detail view of the frame of FIG. 5 secured to a can;

FIG. 9 is a front view of a modified cover;

FIG. 10 is a side view of FIG. 9

FIG. 11 is a cross-sectional view taken on the line 11-11 ofFIG. 9;

FIG. 12 is a partial front view of a further modified form of a flange for holding a cover plate; and

FIG. 13 is a graph showing comparison curves of different methods of stuffing. 1

As shown in FIG. 1, the machine is composed of a frame 10 in which a reel 12 is rotatably mounted by means of a shaft 14 having an indexing means 16 connected to a suitable conventional motor. On top of the frame is a beam 17 supporting-a pair of spaced and similar stands 18 and 18a each of which is associated respectively with a lid of cover plate magazines 20. On the reel are molds 22 for receiving the food. At one of the reel indexed positions is a spraying means 26for spraying the inside walls of an empty mold with liquid releasing oil. Such an oiled mold is indexed by the reel so that it is aligned with a stuffing horn. After the mold has been filled with food and the open end closed by a cover, the filled mold is thenindexed by the reel to a further position where it is manually removed from the reel.

As shown in FIGS. 1 and 2, in posts or stands 18, the piston means 27 is mounted over a cover C for driving a cover plate over the end of a mold as will be described more fully with reference to FIGS. 5 to 12.

As shown in FIG. 3,-the stuffing horn is composed of an outer tube 30 having at one end a threaded fitting 32 for being attached to a food pump and an inner tube 34 telescoped within the outer tube 30. Sealing rings 34a are secured to inner tube 34 and slide on the inner wall of tube 30 which also provides and end bushing 304. A block 34b secured to the end of tube 34 within flexible sealing cup 36 serves as a stop for limiting the movement of the tube 34 adjacent the far cover in a mold to prevent undue distortion of cup 36. The open end of tube 34 is attached to a flexible cup 36 having on its outer surface ribs 38 which extend parallel to the longitudinal axis of tube 34.

Pneumatically actuated lever and latch means 39 is engageable in a notch on tube 34 to assist the final phase step in the withdrawal of tube 34 from a mold, and holding the tube against advancing food pressure while in starting position.

In themodification of FIG. 4, the horn is composed of an outer tube 40 and an inner tube 42 telescoped within tube 40. A threaded fitting 43 is secured to the inlet end of outer tube 40 for attachment to a food pump. A spider 44, FIG. 4a, is mounted on this end of the tube and supports a rod 44a coaxially within the tube. Stop block 44b is slidably mounted on rod. 44a and blocks the inlet end of inner tube 42 when the latter approaches its starting position. Bearing ring 42a is secured to tube 42 and slides on the inner wall of tube 40. Tube 40 has a bearing block 404 at its outer end in which tube 42 slides. Tube 40 has a port 40b to which is attached a compressed air hose 400. Food entering through spider 44 will bear against both bearing ring 42a and block 44b and will start the movement of tube 42 outwardly of tube 40. When block 44b is stopped by nut 44c on rod 44a,.the tube. 42 is .opened to the food pressure, but the friction of the food on the inner wall of the tube 42 prevents the food from actually flowing through the tube until the tube is fully extended and the tube contacts the bottom of mold 22;-

To control the food pressure in the mold, compressed air at a suitable predetermined pressure is introduced through port 40b and pushes against seal assembly 42c to reduce the effect of the frictional drag of the food on the tube 42 and the food stuffing pressure against seal assembly 42b. Thus, for very stiff food that creates a heavy frictional drag on tube 42, the air pressure admitted through port 40b would be higher than for lighter foods that create less frictional drag. a

When the automatic food pressure system of FIG. 40 is used, the compressed air entering port 40b is modulated in response to valve 160. In this system, regulated compressed air is supplied to holding cylinder 104 through pressure regulator 161. Pressure regulator 161 is set as required to obtain the desired food pressure in the mold. For example, if thecross-sectional area of the food mold is 20 square inches, the holding cylinder cross-sectional area is 5 square inches, and the desired food pressure is 12 pounds per square inch, the regulator 161 would be set at 48 pounds per square inch. Thus, the holding cylinder force will hold the mold against the pressure plate 49 until the pressure of the food in the mold exceeds 12 PSI. When this happens, the mold moves to the left to open modulating valve and admit air to the stuffing horn through port 40b until the pressure against the stuffing horn seal ring 420 is sulficient to reduce the food pressure to 12 PSI. The mold then moves toward the pressure plate 49 and reduces the rate of flow of the air to the stuffing horn. In this manner, the air flow to the stuffing horn is modulated as the mold moves to and from the pressure plate 49 such that when the mold moves to the extreme left position the flow through the modulating valve 160 is maximum, and when the mold is held firmly against the pressure plate 49 the flow is zero. Valve 162 is shown held open by force A" during the stuffing operation. When the mold is filled force A is released to shut off the air supply to valve 160 and ex-' haust the air from the stuffing horn through port 40b.

Radially directed ports 45 adjacent the outlet end of tube 42 direct food against flexible cup 46 which also has external ribs 48.

As shown in FIG. 4b, a pressure plate 49 is mounted on the end frame 49a fastened to beam 17, FIG. 1. At the end of a filling stroke, cup 36, or 46, bears tightly against plate 49 and extends slightly into the mold 22 to form a seal to prevent the loss of food pressure in filled mold 22 while the mold is being closed by a cover C, FIG. 2. As the cover C is positioned on the mold 22, the

cover compresses the seal enough to move it out of the path of the cover.

As shown in FIGS. 5 to 8 each mold has at both ends a frame 50 welded to the end of the mold. This frame is adapted to fit over the end of a mold 22 by means of a shoulder 52. As shown in FIG. 5, the inner side of the frame outwardly of a mold has a pair of grooves 54 for receiving a cover plate C.

As shown in FIG. 7, the cover plate is composed of a spring metal plate having flat-end portions 56 and 58, respectively, and a middle center portion 60. When a cover plate C is driven into the grooves 54 as shown in FIG. 6, the plate 60 of spring metal has its curved portion 60 flattened so it seals the end of the mold to prevent the escape of an significant amount of food.- I-Iole 59 serves to receive a hook to pull the cover from the mold in order to remove a cured loaf therefrom.

In the modification of FIGS. 9 to 11, a cover plate C is composed of a flat center portion 90 from which depend a pair of side flanges 92. On the inner side of each so that it contacts. the inner wall of the mold-The pressure of the food then overcomes the friction between the food and the inner wall of the tube so that as the mold is being filled the tube 34 will be retracted. When the mold is filled and substantially at the same time the free edge of the cup 36 reaches the end of the mold, the food pump is shut off, the latch means 39 engages the inner tube 34 to hold thetube 34 in its fully retracted position, and the piston means in stand 18a is activated so as to drive a closing cover plate C into the end of the filled mold. The reel 12 is then indexed away from the horn 30 and the filled mold the manually removed from the reel. At the same time, a new empty mold previously sprayed with releasing oil is brought into position for filling.

With reference to FIG. 4, when an empty mold is ready for stuffing, the food supply pump is started and side flange is mounted a metal leaf spring 94. As shown in FIGS. 10 and 11, each end of a mold has welded thereto a rim 96 for forming a side 96a. When the cover plate C' is driven over the end of the mold, the spring 94 bears tightly against the side 96a of rim 96 so that the cover plate is held firmly onthe mold.

In the modification of FIG. 12, the cover plate C" is a flat metal plate having rounded comers. Aflange 98 is secured to the end of a mold 22 and has side grooves 99 and a bottom groove 99a forming a continuous U- shaped groove. Plate C" is driven down through side grooves 99 and stops with its lower edge seated in bottom groove 99a to tightly seal the mold.

In operation,-the reel 12 is first loaded with empty molds 22 which are manually set in brackets on the rim of the reel. The first mold is then sprayed with releasing oil by the means 26. The reel is indexed to bring this moldinto alignment with the horn 30. Pivoted hook 100, FIG. 1, then moves to the right, hooks onto the mold 22 and pulls the mold to the left against plate 102 in position for receiving a mold cover plate C, C or C". Book 100 is pivotally connected to-the piston rod of holding cylinder 104. Then the piston in stand 18 is activated to drive a cover plate into the end of the mold therebeneath. A clamping cylinder 106 then moves the mold to press the right end of the mold tightly against the pressure plate 49 during the stuffing stroke. with sufilcient pressure to overcome the stufilng force indicated by the arrow 18 caused by the food pressure in the mold. With reference to FIG. 3, when the oiled mold is in the stuffing position the food supply pump is started and the latch means 39 swings to the left and upwardly to release the inner tube 34 such that the inner tube 34 is then advanced into the mold 22 by means of the food pumped into tube 31. The friction of the food on the inner wall of tube 34 along with the food pressure on the inlet end of the inner tube is sufficient to move the tube outwardly of the outer tube while being filled with food. As the cup 36 moves through the mold, the outer edge of the cup is slightly cleared from the inner wall of the mold so that air can escape from the mold. When stop block 34b on tube 34 reaches the cover plate C at the end of the mold the pressure of the food causes the free edge of the cup 36 to expand outwardly as shown in dotted lines in FIG. 3

the latch means 39 disengages the inner tube 42 such that the inner tube 42 is then advanced into the mold 22 by means of food pumped into the tube 40d against the seal 42b and the block 44b. As the tube 42 extends and the block 44 reaches the cover plate C at the end of the mold, as previously described, a modulated flow of compressed air flows into port 40b to control the food pressure in the mold.

When the mold is filled, and at substantially the same time the free edge of the cup 46 reaches the end-of the mold, the block 44b closes off the flow of food into the tube 42, the food pump shuts off and the latch means 39 engages the inner tube 42 to hold the tube 42 in its fully retracted position. Nut 44c can be adjusted as desired to advance or retard the closing of tube 42 as the tube 42 nears its fully retracted position.

The advantages of this invention are first of all in that the food is filled into the mold under pressure. This is made possible by the action of the stuffing horn and by the tight seals given by the cover plates C, C and C" shown in FIGS. 5 to l2.'The food is tightly packed into the mold using about one-half the amount of labor heretofore needed to spray and fill the molds. The loaves are very uniform in cross-section and density along the length of the molds and therefore the stacks of food which have been sliced from theloaves are much more uniform in weight than ordinary. Due to the pressure in the mold, about 5 to 10 percent more food can be filled into the mold than customary. The tight seals given by the covers C and C and C" reduce the normal shrinkage in the luncheon loaves during subsequent cooking.

A comparison of test results on luncheon meats obtained bythis invention with the prior art is given in the curves of FIG. 13. Curve G is according to the instant invention, curve R is for molds ordinarily used by meant process manufacturers and curve H is for the mold of Hawley et al., US. Pat. No. 3,166,007. In making loaves of luncheon meat, every effort is made to reduce the give-away in the finished stacks of meat slices ready for sale. l-Ieretofore, considerable shrinkage has been experienced in the luncheon loaves especially at the ends of the loaves because of moisture loss through loose covers. This shrinkage means that at the end of the loaves there are several stacks of meat which are considerably underweight. This requires manual weight correction to bring them to specified weight. The curve G for the mold of the instant invention shows that for regular molds 27 out of 33 stacks were within a 3/16 02. tolerance, and curve l-l shows that 23 out of 31 stacks were within this tolerance. Curve R shows extreme shrinkage at the righthand end of regular molds, and curve l-l shows extreme shrinkage on the lefthand end of the Hawley et al. mold.

In addition to the desirability of having accurate weights in the stacks of slices, it is also important that the loaves are dimensionally uniform so that the semirigid packaging film will not wrinkle excessively as occur in luncheon meat stacks which are undersized because of the excessive shrinkage at the ends of the loaves.

Shrinkage measuring tests have shown that the average shrinkage for one hundred regular molds of curve R was 7 /5 percent, while the average shrinkage for the molds of this invention was 5 percent, which is a 2 85 percent shrinkage savings for this invention. This amounts to a considerable dollar savings when considering the high volume that the normal meat packer processes. 7

Another advantage is in that, because of the pressure filling of the food into the molds, the molds of this inv'ention can hold from 5 to 10 percent more meat then heretofore used filling methods. This results in an average additional reduction of the whole labor processing costs of about 7 /5 percent.

Having now described the means by which the objects of this invention are obtained,

I claim:

l. A food filling machine comprising mold holding means for holding a mold having an open food inlet end, pressure movable stuffing horn means for entering said mold through said inlet end and over the length of said mold for filling said mold with food as it is being withdrawn from said mold, and piston means at said inlet end to apply a cover plate for closing said inlet end after said horn means has been withdrawn from said mold.

2. A machine as in claim 1, further comprising means for holding pressure on the food in the mold while said cover plate closes said inlet end.

3. A machine as in claim 1, further comprising means for controlling the pressure on said food while said food is being filled into the mold.

. 4. A machine as in claim 3, further comprising means for holding pressure onthe food in the mold while said cover plate closes said inlet end.

5. A machine as in claim 1, further comprising flexible cup means secured to the outlet end of said horn means.

6. A machine as in claim 5, said horn means having a longitudinal axis, and ribs on the outer surface of said flexible cup means extending substantially parallel to said longitudinal axis. v

7. A machine as in claim 1, further comprising means for applying liquid release oil into an empty mold prior to being filled with food.

8. A machine as in claim 1, said horn means comprising a telescopic hollow inner tube within an outer tube having a longitudinal axis and having a food inlet end an afood tlete d.

zA madhine as in claim 8, further comprising compressed air means for applying air pressure on said inner tube as it is withdrawn from themold.

10. A machine as in claim 9, further comprising air pressure flow control means for controlling the pressure on the food as said inner tube is withdrawn from the mold.

11. A machine as in claim 8, said inner tube being spaced from said outer tube, sealing ring means fastened to said inner tube and engaging the inner wall of said outer tube, and bearing means on said outer tube for slidably supporting said inner tube.

' 12. A machine as in claim 9, further comprising port means in said outer tube for supplying compressed air into said space, and stop block means in said outer tube for closing the food inlet end of said inner tube when said inner tube is fully retracted into said outer tube.

13. A machine as in claim 1, said cover plate including a spring metal cover plate having flat end portions and areuate middle portion for being spring seated in grooves at the inlet end of a mold.

14. A machine as in claim 1, said cover plate including a flat plate, flanges depending from opposite side edges of said plate, and spring means on said flanges for engaging the end sides of a mold to hold the plate tightly against the inlet end of the mold.

15. A machine as in claim 1, said cover plate including a flat cover plate for being seated in side and bottom grooves at the inlet end of said mold.

* =k IR I I! 

1. A food filling machine comprising mold holding means for holding a mold having an open food inlet end, pressure movable stuffing horn means for entering said mold through said inlet end and over the length of said mold for filling said mold with food as it is being withdrawn from said mold, and piston means at said inlet end to apply a cover plate for closing said inlet end after saId horn means has been withdrawn from said mold.
 2. A machine as in claim 1, further comprising means for holding pressure on the food in the mold while said cover plate closes said inlet end.
 3. A machine as in claim 1, further comprising means for controlling the pressure on said food while said food is being filled into the mold.
 4. A machine as in claim 3, further comprising means for holding pressure on the food in the mold while said cover plate closes said inlet end.
 5. A machine as in claim 1, further comprising flexible cup means secured to the outlet end of said horn means.
 6. A machine as in claim 5, said horn means having a longitudinal axis, and ribs on the outer surface of said flexible cup means extending substantially parallel to said longitudinal axis.
 7. A machine as in claim 1, further comprising means for applying liquid release oil into an empty mold prior to being filled with food.
 8. A machine as in claim 1, said horn means comprising a telescopic hollow inner tube within an outer tube having a longitudinal axis and having a food inlet end and a food outlet end.
 9. A machine as in claim 8, further comprising compressed air means for applying air pressure on said inner tube as it is withdrawn from the mold.
 10. A machine as in claim 9, further comprising air pressure flow control means for controlling the pressure on the food as said inner tube is withdrawn from the mold.
 11. A machine as in claim 8, said inner tube being spaced from said outer tube, sealing ring means fastened to said inner tube and engaging the inner wall of said outer tube, and bearing means on said outer tube for slidably supporting said inner tube.
 12. A machine as in claim 9, further comprising port means in said outer tube for supplying compressed air into said space, and stop block means in said outer tube for closing the food inlet end of said inner tube when said inner tube is fully retracted into said outer tube.
 13. A machine as in claim 1, said cover plate including a spring metal cover plate having flat end portions and arcuate middle portion for being spring seated in grooves at the inlet end of a mold.
 14. A machine as in claim 1, said cover plate including a flat plate, flanges depending from opposite side edges of said plate, and spring means on said flanges for engaging the end sides of a mold to hold the plate tightly against the inlet end of the mold.
 15. A machine as in claim 1, said cover plate including a flat cover plate for being seated in side and bottom grooves at the inlet end of said mold. 